chg: [gitchangelogrc] match sub version of tags

.gitchangelog.rc

@@ -140,7 +140,7 @@ subject_process = (strip |
 ##
 ## Tags that will be used for the changelog must match this regexp.
 ##
-tag_filter_regexp = r'^v[0-9]+\.[0-9]$'
+tag_filter_regexp = r'(^v[0-9]+\.[0-9]$)|(^v[0-9]+\.[0-9]\.[0-9]$)'
 
 
 ## ``unreleased_version_label`` is a string